There are many types of propellers adapted for use with watercraft motors. Each propeller is designed to be suitable for an intended use, such as for high speed, high torque, use in a weedy environment and so forth. From a mechanical standpoint, the propeller is secured to a drive shaft for rotation therewith. To prevent damage to the motor and drive shaft should the propeller engage an obstruction or fixed object, the drive shaft is typically provided with a shear pin which is disposed through a bore defined radially through the drive shaft. The propeller is adapted about the drive shaft and engages the shear pin such that the propeller is rotatably driven by the extensions of the shear pin. Should the propeller engage a fixed structure or obstruction, such as a rock, tree limb, stump or the bottom of a lake, the shear pin is mechanically constructed to deform or break, thereby momentarily or permanently disengaging the propeller from the drive shaft to avoid damaging the engine or drive shaft. Thus, the propeller will cease to rotate, either temporarily or permanently, due to the deforming or breaking of the shear pin. In essence, the shear pin is the safety mechanism or "circuit breaker" that prevents damage to the engine and drive shaft driving the propeller.
When the shear pin becomes damaged or broken, replacement of the pin is necessary. If the shear pin becomes damaged or bent, typically the propeller will vibrate and generate excessive vibration and noise which is noticeable to the operator and renders the operation of the propeller inefficient. Removing and replacing the shear pin is cumbersome and difficult for the operator. Often, it is difficult to remove the propeller from the drive shaft due to the location of the propeller with respect to the boat and the operator, and, due to the fact that the propeller often becomes jammed against the drive shaft due to the damage of the shear pin. Often times, a boat operator will attempt to remove the jammed propeller to gain access to the shear pin by using conventional tools, such as screwdriver, to leverage the propeller from the drive shaft. Often times, this leveraging damages and renders totally useless the propeller since the propeller is often comprised of plastic and can become cracked. One conventional prior art propeller implementing a shear pin is described in U.S. Pat. No. 4,482,298 which discloses a weedless propeller, the teachings of which are incorporated herein by reference. One embodiment of this propeller is shown in FIGS. 1-3 of the present application. This propeller is widely used throughout the industry. Unfortunately, this propeller is prone to damage if not removed properly, as it is typically comprised of plastic and cracks when the operator attempts to remove the propeller to gain access to the damaged shear pin.
The present invention sets forth a tool to facilitate effectively removing a propeller from the corresponding drive shaft when the shear pin becomes broken or damaged.